Description:NSPI Proxy encountered an error while receiving a packet. The target Domain Controller or the network or a client might be down. The winsock subsystem returned the error:[<error code>]. The circuit that received this error is being closed.

Comments:Peter Van Gils
This event is logged when you're running Exchange Server 2007 and HKLM\System\CurrentControlSet\Services\TCPIP\Parameters\MaxUserPort is set lower than 60000. ExBPA will recommend keeping this on the default 60000. See “MaxUserPort Key is Missing or Non-default” for additional information on this issue.
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5

EventID.Net
This event is logged whenever a Collaboration Data Objects (CDO) script that opens a MAPI session runs on the server that is running Exchange Server 2003 SP1. See ME912062 for additional information about this event.
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3

EventID.Net
As per Microsoft: "This event indicates that the NSPI interface of the Exchange server encountered a problem when communicating with a global catalog server. This problem may be a transient one. However, if this event is logged repeatedly, then further investigation would be needed". See MSEX2K3DB for details on this event.
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